CyberPower Systems (CPS) know how

Intro

CPS devices and their clones/rebrands/siblings are quite popular, so it is inevitable some issues crop up and become well-known. This page hopes to summarize some of them. Some information contributed by the community ended up in NUT documentation or GitHub issues and "TL;DR" of it is adapted here. See also direct reports labeled as CyberPower (CPS)

Regular disconnections

See links from https://github.com/networkupstools/nut/wiki/Troubleshooting-eventual-disconnections-(Data-stale)

• Notably the Arch Linux page on NUT has a lot of details

Discrete offdelay setting (shutdown timer)

• https://github.com/networkupstools/nut/blob/master/docs/man/usbhid-ups.txt#L57-L66

... many Cyber Power Systems (CPS) models tend to divide this delay by 60 and round down (e.g. setting 30 means 0 to firmware), so the minimum advisable value is 60 to avoid powering off immediately after NUT sends the shutdown command to the UPS.

Discrete battery.charge.low setting

• https://github.com/networkupstools/nut/issues/520#issuecomment-870831642

I've noticed that with one Cyberpower model... not this one, (PR1000LCDRTXL2U) that only certain values for battery.charge.low are allowed. Anything outside of the set of allowed values are rounded or ignored.

For that model, the only allowed values are [60,55,50,45,40,35,30,25,20]

So in some cases, your UPS may not support a value of e.g. 10 for the battery.charge.low setting.

A bash loop like this can help you map out the allowed values.

:; for i in {90..0}; do \
       echo "set to $i"; upsrw -s battery.charge.low=$i -u * -p * cps-big; sleep 1; \
       upsc cps-big battery.charge.low; echo ""; \
   done